Normal approximation to binomial

In the following question I know that I am supposed to use the normal approximation to the binomial which we have covered in class but I am not sure how to apply it here.

It has been statistically determined that 65% of the new chicks of a bird can survive winter. What is the minimum number of chicks to hatch before winter such that there is a 80% probability that at least 6 will survive.

In the following question I know that I am supposed to use the normal approximation to the binomial which we have covered in class but I am not sure how to apply it here.

It has been statistically determined that 65% of the new chicks of a bird can survive winter. What is the minimum number of chicks to hatch before winter such that there is a 80% probability that at least 6 will survive.

Thank you

Start by defining your random variable: Let X be the random variable number of chicks that survive hatching.

Define the distribution followed by X: X ~ Binomial(n = ?, p = 0.65).

Write a probability statement that encapsulates the question: Find the minimum value of n such that .

Using trial and error (or, even better, technology) it doesn't take long to get n = 11. I don't see why the normal approximation would be required here.

In the following question I know that I am supposed to use the normal approximation to the binomial which we have covered in class but I am not sure how to apply it here.

It has been statistically determined that 65% of the new chicks of a bird can survive winter. What is the minimum number of chicks to hatch before winter such that there is a 80% probability that at least 6 will survive.

Thank you

Suppose that chicks hatch, the number that survive , you are asked to find the smallest so that where is that probability that there are or more survivours.

Using the normal approximation the number of survivours is to be treated as a normal random variable with mean and SD .